Effect of haemoglobin levels on outcome in intravenous thrombolysis-treated stroke patients

Abstract

Introduction Alterations in haemoglobin levels are frequent in stroke patients. The prognostic meaning of anaemia and polyglobulia on outcomes in patients treated with intravenous thrombolysis is ambiguous. Patients and methods In this prospective multicentre, intravenous thrombolysis register-based study, we compared haemoglobin levels on hospital admission with three-month poor outcome (modified Rankin Scale 3–6), mortality and symptomatic intracranial haemorrhage (European Cooperative Acute Stroke Study II-criteria (ECASS-II-criteria)). Haemoglobin level was used as continuous and categorical variable distinguishing anaemia (female: <12 g/dl; male: <13 g/dl) and polyglobulia (female: >15.5 g/dl; male: >17 g/dl). Anaemia was subdivided into mild and moderate/severe (female/male: <11 g/dl). Normal haemoglobin level (female: 12.0–15.5 g/dl, male: 13.0–17.0 g/dl) served as reference group. Unadjusted and adjusted odds ratios with 95% confidence intervals were calculated with logistic regression models. Results Among 6866 intravenous thrombolysis-treated stroke patients, 5448 (79.3%) had normal haemoglobin level, 1232 (17.9%) anaemia – of those 903 (13.2%) had mild and 329 (4.8%) moderate/severe anaemia – and 186 (2.7%) polyglobulia. Anaemia was associated with poor outcome (ORadjusted 1.25 (1.05–1.48)) and mortality (ORadjusted 1.58 (1.27–1.95)). In anaemia subgroups, both mild and moderate/severe anaemia independently predicted poor outcome (ORadjusted 1.29 (1.07–1.55) and 1.48 (1.09–2.02)) and mortality (ORadjusted 1.45 (1.15–1.84) and ORadjusted 2.00 (1.46–2.75)). Each haemoglobin level decrease by 1 g/dl independently increased the risk of poor outcome (ORadjusted 1.07 (1.02–1.11)) and mortality (ORadjusted 1.08 (1.02–1.15)). Anaemia was not associated with occurrence of symptomatic intracranial haemorrhage. Polyglobulia did not change any outcome. Discussion The more severe the anaemia, the higher the probability of poor outcome and death. Severe anaemia might be a target for interventions in hyperacute stroke. Conclusion Anaemia on admission, but not polyglobulia, is a strong and independent predictor of poor outcome and mortality in intravenous thrombolysis-treated stroke patients.

Both Ends of Values in the Hemoglobin Spectrum Are Associated with Adverse Stroke Outcomes

“…Most studies have shown that anemia on admission, after adjusting for various covariates including NIHSS, still predicts adverse outcomes after stroke, even in patients who have already received intravenous thrombolysis [12], except for 1 study [13]. Opposite to anemia, studies on the effect of high hemoglobin values on adverse stroke outcomes are rare and inconsistent [2, 4].…”

“…Consistent with previous studies, our study also found patients with anemia were more likely to be older, have atrial fibrillation, and have CHD [17]; high hemoglobin was more common in ever smoking and heavy alcohol patients [4] (Table 1). Also, previous studies have found that patients with anemia were more likely to have more severe stroke, and after adjusting for various covariates including NIHSS, the relative impact of anemia on poor stroke outcomes will be reduced [5, 12]. Considering the impact of NIHSS on the relationship between anemia and adverse stroke outcomes, although we have adjusted for these risk factors in our multivariable analysis, potential residual confounding effects and possible effect of comorbid disease which associated with abnormal hemoglobin values could not be completely excluded.…”

A Novel Mobilization Criteria Checklist 12 to 24 Hours After Intravenous Thrombolysis in Acute Ischemic Stroke

“…This may include identifying downtrends in hemoglobin (Hgb) 33,36. Although no evidence supports that anemia (less than reference values)33 is associated with hemorrhagic transformation, the overall outcomes are poorer 37. As mentioned, blood pressure stability within set parameters is important.…”

“… Intracranial or extracranial stenosis 22  Visible acute infarct 17 3) Hemodynamic instability: 1,5  Signs of active bleeding, or drop in hemoglobin 33,36,37  SBP <90 or >180 mm Hg, or out of set parameters 28,32  DBP > 105 mm Hg 1…”

“…Standard laboratory values were assessed. 33 Partial thromboplastin time and hemoglobin (Hgb) were within normal limits, 1,33,37 and blood glucose was 108 mg/dL. Upon review of items (4) and (5), no indications of serious comorbid medical illnesses or unstable cardiac conditions were recorded.…”